Thai Police Maj. Gen. Misakawan Buara, commander of a division that handles environmental crimes, said the two women, Chintana Fahpratanporn and Chittima Chaiyakul, were picked up Sunday in a raid on ivory shops in Nakhon Sawan province.

Police believe the women supplied African ivory to Samart Chokchoyma, a Thai national who U.S. and Thai prosecutors say sold several pieces of ivory on EBay from September 2006 to November 2006 to Moun Chau of Montclair. He allegedly disguised the shipments as gifts and toys.

The women have been charged with selling and possessing illegal ivory.

Samart, who lives in Thailand, and Chau were charged Tuesday in Los Angeles with violating an international treaty that protects endangered species. Samart has already been charged under Thai law with violating the country's Wild Animal Reservation and Protection Act.

The U.N. Convention on International Trade in Endangered Species in 1989 banned all international ivory trade. But in recent years, poaching in central and eastern Africa has intensified with much of the illegal ivory exported to Thailand, Vietnam and China, where it is carved into jewelry, trinkets and statues for locals as well as foreign tourists.

Traders in Thailand have thrived in part because the 1989 ban did not address domestic trade. That loophole allows them to deceive authorities by claiming their African ivory came from domestic sources -- a tactic that is effective because it can be difficult without DNA testing to tell the difference between African and Asian ivory.

Authorities say 10 tons of African ivory was seized in Southeast Asia last year, including at least 2 tons from a Thai airport in a single bust.

U.S. authorities said investigators seized several ivory specimens from a business owned by Chau in Claremont. DNA testing determined the ivory had come from Africa.

In their raid, Thai authorities said they seized six ivory tusks they suspect came from Africa worth an estimated $30,222. DNA testing has not been conducted on that ivory.

"This case demonstrates the power of cooperative law enforcement efforts, not only to enforce the law but to protect animal species that are threatened with extinction," Acting U.S. Atty. George S. Cardona said in a statement.

Samart remains free on bail in Thailand awaiting trial on the Thai charges, which carry a maximum four-year jail sentence and a fine of up to $1,200. The two women arrested Sunday face the same punishment as Samart.

After he is prosecuted in Thailand, Samart could then be extradited to the United States to face additional charges that carry a sentence of up to 53 years in prison. Chau, meanwhile, faces up to 25 years in federal prison if convicted. Chau will be summoned to appear for arraignment next month.

Steve Galster, the executive director of the conservation group Freeland, which assisted the Thai police in the investigation, said he expects the raids will slow but not stop the ivory trade in Thailand.

"We hope authorities keep working up the chain to put the kingpins of this destructive, multibillion trade behind bars before the world is permanently robbed of elephants and endangered species," he said.